Cone-type loud-speaker



.May 14, 1929. F. c. BARTON 1,713,210

coNE TYPE LOUD SPEAKER Fil ed Dec. 14, 1926 2 Shet-Sheet 1 I Inventor-I 'F'r'edericKCBaPtofl, bg Hls Attorney May 14, 1929. F. c. BARTON 1,713,210

' coma TYPE LOUD SPEAKER Filed Dec. 14, 1926 1 2 Sheets-Sheet 2 MW um HIS [Atto ney].

Patented May .14, 1929.

- UNITED STATES rnnnnnrcx c. BARTON, or. SCHENECTADY, NEW YORK,

ASSIGNOR T GENERAL ELEC-V TRIC COMPANY, A CORPORATION OF NEW YORK.

CONE-TYPE toun-srnaxnn'.

- Application filed December 14, 1926. Serial'No. 154,814.

My plesent invention relates to sound reproducing devices of the type commonly known as loud speakers and more particularly to the type of reproducing 'devicesemploying a vibrating conical diaphragm. I

It is one of the objects of my invention to provide an improved flexible support for a vibrating cone diaphragm. Another object of my invention is to provide a loud speaker having a smaller-vibrating diaphragm than that usually emplo ed and which shall be efficient, rugged an capable of manufacture at moderate cost. T

The novel features whch I believe to be characteristicof my invention are set forth with particularity in the appended claims. My invention itself, however, will best be understood from reference to the following specification taken in connection with the accompanying drawing in which Fig. 1 repl resents a rear View of a cabinet with a loud speaker mountedtherein which embodies the features of my invention; Fig. 2 is a detail sectional, viewof the drive mechanism for the vibrating diaphragm and" a portion of the diaphragm; Fig. 3 is an exploded per- 'spective view .of the armature of the actuat- 111g mechanism and the connection betweenthe armature and vibrating diaphragm; Fig. 4 is a front view partly broken away of the loud speaker unit; Fig. 5 is a plan View of the conical paper diaphragm before the ends thereof have been secured together; while Fig. 6 is a detail sectional view of the mounting for the diaphragm. I

Referring to the drawing, I have indicated at 1 acabinet having a front panel 2 provided with an opening 3 within which a diaphragm 4 may be mounted. Opening 3 may.

be covered by a sheet of woven or other suitable material 3'. The diaphragm 4 consists of a paper or fibrous cone about six.

mils in thickness and is provided with coaxial circumferential corruglations 5 spaced apart approximately 4 inc each corrugationhaving a diameter of about Mich. The cone has an outwardly extending flange 6 at its-basewvhich is cut, on radial lines 7 to provide aseries of tabs 8 extending out- I wardly around the flange. The tabs Sextend substantially across the entire width of fiangefi and are approximately 1/ inch in width and %'inch in length. 1

A relatively heavy reenforcing paper or fiber ring 9 isarranged parallel to flange 6 and secured thereto at the outer end'of the tabs provldlng the flange with a certain degree of rigidity. A metal ring 10 of aluminum or other material is secured to the reenforced portionv of the cone and .flange. Ring 10 and the reenforced portion ofthe flange 6 are secured-between the panel 2 and a metal plate 11 mounted on the insideof panel 2. v

A metal plate 12 provided withan open- .ing 13 is spaced from but secured to plate 11 and provides a mounting for the actuat-- mg mechanism for the diaphragm. The

actuating mechanism or motor comprises'a permanent magnet 14 provided pieces 15 and 17 vibrates. The armature 17 is mounted on a spring support 18.and is reduced in cross with pole section at one end thereof, as indicated at I 19 in Fig. 3, andconnected to a hollow copper'drive rod 20. The end 21 of the drive rod, which'is adjacent the armature, is flattened and provided with an opening 22 16 between which an armature which fits over the reduced end of armature 17 and is soldered thereto. A brass plug 23 havin an enlarged end portion 24 is sweated into the opposite end of drive rod 20. w The vibrating cone 4 is provided at its apex with an opening 25. A thin metal spider 26 having a central opening 27 is cemented to the cone and connected to the drive rod 20 by means of a small screw threaded bolt 28 which engages plug 23. The flat orenlarged portion 24 of plug 23 gives a. substantial bearing for the driverod against the diaphragm and at the same time providesmeans for the engagement of the screw bolt 28. The hollow cop er drive rod 20 is strong yetflexible and its attened end portion reduces the tendency of the cone 4 to vibrate laterally due to the angular motion of the armature.

The provision of clrcularcorrugations on the cone reduces the tendency of the cone to rattle at certain frequencies. Although I have found that unusually good results may be obtained-with a thin paper c'one having a base seven inches in diameter and an angle at the apex of 105, both of these dimensions may be varied slightly both above and below the figures given. In general the base of the cone will not' be less than six and one half inches nor more than seven and one half inches, while the angle at the apex will usually be at least 100 and not more than 110.

The conical diaphragm may be developed with an angle at the apex of 105 and a base having a diameter of approximately nine inches. The cone may then be cut back to provide the tabs 8, the cuts being spaced approximately inch apart providing tabs approximately inch long. The tabs, when pressed outwardly, provide a flexible supporting flange 6 and a cone having a base of approximately seven inches. The employment of a relatively small vibratingcone together with an integral flexible support therefor effects a substantial economy in the cost of manufacture, and at the same time provides a device highly efficient in operation and rugged in construction.

\Vhat I claim as new and desire to secure by Letters Patent of the United States, is 1. Ina sound reproducing device, a conical diaphragm having an integral outwardly ex tending flange at the base thereof, an armature, and means comprising a hollow rod connected between said armature of said cone. 2. In a sound reproducing device, a conical diaphragm of fibrous material, said diaphragm having an outwardly extending flange at the base thereof, said flange comprising a series of radially extending tabs whereby the diaphragm may be flexibly supported and a reenforcing fibre ring arranged parallel to the flange and secured to the outer portion thereof.

3. A sound producing device comprising a diaphragm, a vibratory member, and a hollow rod connected to said diaphragm at one of its ends and provided at the other of its ends with a flattened portion including an opening arranged to receive one end of said member.

In witness whereof, I have hereunto set my hand this 13th day of December, 1926.

FREDERICK C. BARTON.

and the apex 

